Modular handguard device for a firearm

ABSTRACT

A modular handguard device configured to be slidably mated to an outer surface of an existing or affixed handguard. The handguard of the present invention may be configured to mate with any handguard to provide an extension of the handguard for purposes including mitigation of detectable heat signature, operator safety and increased reconfigurability of firearms for mission specific needs.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit to provisional patent application No.62/360,924, entitled “MODULAR HANDGUARD DEVICE FOR A FIREARM”, filedJul. 11, 2016, which is incorporated by reference in its entirety forall purposes.

FIELD OF THE INVENTION

The present invention pertains in general to shielding of surfaces asassociated with firearms with elevated surface temperatures with a heatmitigation and shielding device to reduce the risk of injury to anoperating user.

BACKGROUND OF THE INVENTION

Firearms are weapons designed to fire a projectile, or round, at a highrate of speed toward an intended target. A rapidly combusting orexplosive charge is initiated within the firearm to generate a rapidlyexpanding gas, which is controlled and directed through a barrel. Therapidly expanding gas propels a projectile out of the muzzle-end of thebarrel at high velocity. The combustion of the explosive charge withinthe firearm subjects parts of the firearm to high pressures andtemperatures.

A common problem with operation of a firearm surrounds elevated surfacetemperature of parts of the firearm. Parts which are in contact with theexplosive charge used to fire a projectile from the firearm typicallyexhibit the highest surface temperatures. According to ASTM C1055(Standard Guide for Heated System Surface Conditions that ProduceContact Burn Injuries), an average person may touch a 60° C. (140° F.)surface for up to 5-seconds without sustaining an irreversible burn.When considering metallic surfaces, as commonly found on a firearm,contact with a surface over 70° C. (158° F.) results in nearinstantaneous tissue damage. Some portions of a firearm may exhibittemperatures in excess of 426 ° C. (800° F.).

Direct contact with a surface having elevated temperatures, such as bythe operator or others in near proximity of the firearm, may causeinjury and/or distraction to the operator. Distractions in certainscenarios, such as covert operations or dynamic threat situations, canresult in life-threatening consequences or mission failure. Distractionsis such scenarios may cost an operator their life, or the life of thosesurrounding the operator—such as members of the operator's team.

Due to the nature of a firearm, each explosive charge associated with afired round transfers heat energy into parts of the firearm. This heatenergy transfer increases the surface temperature of firearm surfacesbeyond safe levels. Contact with such surfaces may injure or distractany individual that contacts such a surface. Furthermore, such surfacesincrease in temperature with the firing of additional rounds, and thetemperature increases more rapidly as rounds fired from the firearm arefired in more rapid succession.

SUMMARY OF THE INVENTION

Handguards are devices affixed to a firearm, typically long-arms, whichserve many purposes. One purpose of a handguard is to protect anoperator and those in close proximity from injury due to contactingsurfaces with elevated temperature surfaces, particularly firearmbarrels. Handguards also provide attachment points to mount peripheraldevices such as fore-grips, flashlights, and laser sights. Handguardsalso shield accessories that may be heat-sensitive from excess heat.

As barrel length varies according to intended purpose, so do handguards.For instance, a short barrel may be used for increased maneuverabilityin close-quarters battle such as within a building. A longer barrel maybe used for increased accuracy and precision for more distant targets.It is common for an operator to change a barrel within the scope of asingle mission. Changing barrels to a longer barrel exposes more barrelsurface, which may reach elevated temperatures and injure the operatoror others in near proximity. It is common for an operator to add asuppressor, such as disclosed in U.S. application Ser. No. 15/408,224,Firearm Suppression Device, to Garst, et al., incorporated in itsentirety by reference. Adding a suppressor extends the effective lengthof a barrel and exposes surfaces, which may reach elevated temperaturesand injure the operator or others in near proximity. Changing barrels toa shorter barrel may result in the handguard extending beyond themuzzle-end of the barrel. In certain scenarios, a handguard that extendsbeyond the muzzle end of a barrel allows an operator to grasp a firearmin close-proximity to the muzzle end of the firearm. Grasping a firearmin close-proximity to the muzzle-end may expose the operator topotential injury from direct exposure to the muzzle blast of thefirearm. Furthermore, a handguard that extends beyond the muzzle end ofa firearm may result in a firearm that is heavier than necessary, andlonger than necessary. A firearm that is longer than necessary istypically more difficult to maneuver in situations such as those thatthe operator is within a building or vehicle.

The present invention surrounds a device to provide a modular handguardfor use with existing firearms having affixed handguards to mitigate therisk of injury surrounding contacting surfaces of elevated temperature.It will be appreciated that an affixed handguard is a handguard affixedto a firearm or firearm barrel, typically with tools, fasteners, oradapters. An exemplary affixed handguard is disclosed by U.S. PatentApplication No. 2014/0130390, Modular Rifle Handguard, to Geissele(“Geissele”), incorporated by reference in its entirety.

Certain embodiments of the present invention surround a modularhandguard, providing an extension of affixed handguards to alleviateproblems associated with elevated surface temperatures. Certainembodiments of the present invention are manufactured from materialcompositions with heat mitigating characteristics. Materials having heatmitigating characteristics typically have low heat transfer properties.Materials having low heat transfer properties have reduced transmittanceof heat energy through the material. The use of such a material in themanufacture of a modular handguard limits the transfer of heat energy toan external surface of a modular handguard, thus mitigating the externalsurface temperature of a modular handguard. Such material compositionsmay comprise ceramic, polymeric or other materials with a low heattransfer coefficients. In certain embodiments, a modular handguardcomprises a polymeric material, and it may be preferred that the polymerhas a melting point above 200° C. (392° F.).

Certain embodiments comprise a modular handguard having an additionalheat mitigation feature such as an intermediate insulative barrier. Anintermediate insulative barrier is applied as a buffer of reduced heattransfer properties between a modular handguard and portions of anaffixed handguard or firearm. Intermediate insulative barriers reducethe transmittance of heat from a firearm to an outer surface of amodular handguard which an operator may contact. An intermediateinsulative barrier may comprise a material having lower heat transferproperties than materials from which the firearm or affixed handguardare made. Other forms of an intermediate insulative barrier include asealed volume comprising a pressure lower than that of the ambientenvironment such as a partial vacuum or full vacuum. Alternativeembodiments comprise an additional heat mitigation feature comprisingstrategic air-pockets designed to prevent or mitigate the passage ofheat.

The modular handguard of the present invention may shield parts of afirearm, reducing detectable heat signature. Detectable heat signatureis typically associated with infrared radiation from surfaces havingelevated surface temperatures. Detectable heat signature, transmitted bysurfaces with an elevated temperature such as a barrel or suppressor, isundesired in certain scenarios. It will be further appreciated that amodular handguard made from material having heat mitigatingcharacteristics may further reduce detectable heat signature.

Certain embodiments comprise a modular handguard configured to slidablyinterface with an affixed handguard while maintaining a similar outersurface boundary as the affixed handguard. A modular handguard asdisclosed, typically mates with an outer surface of an affixedhandguard. However, it will be appreciated that a modular handguard mayslidably interface with an internal or outer surface of an affixedhandguard.

Certain embodiments comprise a modular handguard incorporatingattachment features including but not limited to: a tactical rail,Picatinny Rail as defined by MIL-STD-1913 (Military Standard[MIL-STD]-1913, Dimensioning of Accessory Mounting Rail for Small ArmsWeapons, Department of Defense, 3 Feb. 1995), KeyMod rails and/or M-Lok®rails. It will be appreciated that the modular handguard may utilizeattachment features known to those skilled in the art surrounding theaffixing of accessories to firearms. It will be further appreciated bythose skilled in the art that a modular handguard may include aplurality of attachment features.

Certain embodiments of the present invention comprise a modularhandguard incorporating electrically powered elements, such as lights,at the distal end of the handguard. The lights may be integrated intothe body of the modular handguard during the manufacturing process. Itwill be appreciated that optical imaging capability and otherelectrically powered elements may be integrated into the body of themodular handguard. Certain technologies provide power to electricallypowered elements with electrical connections such as those disclosed byU.S. Pat. No. 7,627,975 to Hines (“Hines”). However, Hines is limited toproviding power to peripheral devices mounted to an attachment featureof an attached handguard. Hines does not provide power to peripheraldevices mounted to a slidably attached handguard, such as the modularhandguard of the present invention. Furthermore, Hines does not disclosethe use of integrated lighting elements in a distal end of a handguard.It will be further appreciated that electrical transmission elements,such as wires, may be integrated into the body of a modular handguardfor connection to an electrical power source, such as a battery. Suchelectrical transmission features provide electrical transmittancethrough mediums known to those skilled in the art, such as pressureconnectors or mechanical interlock connectors. Transmission ofelectrical power through the modular handguard allows for the supply ofremote power for the operation of integrated or attached peripheraldevices. Additionally, integrated electronics and accessories mayinclude various energy harvesting and energy storage capabilities knownto those skilled in the art.

These and other advantages will be apparent from the disclosure of theinventions contained herein. The above-described embodiments,objectives, and configurations are neither complete nor exhaustive. Aswill be appreciated, other embodiments of the invention are possibleusing, alone or in combination, one or more of the features set forthabove or described in detail below. Further, this Summary is neitherintended nor should it be construed as being representative of the fullextent and scope of the present invention. The present invention is setforth in various levels of detail in this Summary, as well as in theattached drawings and the detailed description below, and no limitationas to the scope of the present invention is intended to either theinclusion or non-inclusion of elements, components, etc. in thisSummary. Additional aspects of the present invention will become morereadily apparent from the detailed description, particularly when takentogether with the drawings, and the claims provided herein.

BRIEF DESCRIPTION OF FIGURES

FIG. 1—A perspective view of certain embodiments of a modular handguard

FIG. 2A—A cross-sectional view of certain embodiments of a modularhandguard

FIG. 2B—A cross-sectional view of certain embodiments of an affixedhandguard

FIG. 3A—A perspective view of certain embodiments of a modular handguardprior to assembly with an affixed handguard

FIG. 3B—A perspective view of certain embodiments of a modular handguardprior to assembly with an affixed handguard

FIG. 3C—A perspective view of certain embodiments of a modular handguardassembled with an affixed handguard

FIG. 4A—A view of a second end of certain embodiments of a modularhandguard

FIG. 4B—A side view of certain embodiments of a modular handguard

FIG. 4C—A view of a first end of certain embodiments of a modularhandguard

DETAILED DESCRIPTION

Certain embodiments of the invention comprise a modular handguardconfigured to be disposed over a barrel or suppressor component at adistal end of a barrel. Such embodiments of the modular handguard areconfigured to mate with an affixed handguard. The modular handguardmitigates accidental contact with distal surfaces of a firearm havingelevated temperature such as a barrel or suppressor affixed to thefirearm.

It will be appreciated that an affixed handguard may comprise anexisting handguard comprising aluminum or steel, or a heat mitigatinghandguard as disclosed in U.S. application Ser. No. 14/932,924, HeatMitigating Handguards for Rifles and Method of Manufacture Thereof, toGarst (“the '924 Application”), incorporated by reference in itsentirety.

Certain embodiments comprise a modular handguard comprising a heatmitigating material composition with a low heat transfer coefficient.Certain embodiments of the present invention are manufactured frommaterials and heat mitigating strategies as disclosed by the '924Application. Certain embodiments of the present invention may compriseceramic, polymeric or other materials with a low heat transfercoefficient.

In certain embodiments of the present invention, as shown in FIG. 1, amodular handguard 100 has a hollow form and further comprises an outerform 110 having a first end 111 axially offset from a first end 121 ofan inner form 120. The outer form 110 further comprises an opening 112.The outer form 110, spans the entire length of the modular handguard100, while the inner form 120 is shorter than the outer form 110. Thisresults in an offset between the inner form 120 and an outer form 110,such that the first end 121 of the inner form is inset from the firstend 101 of the modular handguard. The outer form 110 further comprisesan outer surface 115 and an inner surface 118. The inner form 120further comprises an outer surface 125, coincident with the innersurface 118 of the outer form.

Shown in FIG. 2A and FIG. 2B, a modular handguard 100 has an inner form120 of substantially similar cross-sectional profile as an attachedhandguard 200. An outer profile dimension 1130 of the inner form 120(FIG. 2A) is substantially similar to an outer profile dimension 2130 ofan affixed handguard 200 (FIG. 2B). The inner surface 118 of the outerform, referenced in FIG. 1, is configured to slidably mate with theouter surface 205 of the attached handguard, referenced in FIG. 2B. Thisslidable mating is typically performed with an engineering fit. It willbe appreciated that an engineering fit may comprise a running fit,locational clearance fit, RC fit, or other engineering fits such asthose specified by ANSI B4.1 (Standard Tolerance Limits and Fits). Itwill be further appreciated that other engineering fits or assemblystrategies known to those skilled in the art may be used whilemaintaining the inventive spirit of the present invention.

In certain embodiments of the present invention, as shown in FIG. 1, anouter form 110 is offset along a longitudinal axis 105, from an innerform 120. As a result, the inner form 120 is inset from a first end 101of the modular handguard. This inset provides a surface orthogonal tothe longitudinal axis 105 of the modular handguard 100 inset from thefirst end 101 of the modular handguard. This orthogonal surface servesas a mechanical stop 130. The mechanical stop 130, inset from the firstend 101 of the modular handguard 100, provides an abutting surface foran affixed handguard 200 (FIG. 3A-3C) when mated with the modularhandguard 100.

Certain embodiments of the present invention, as seen in FIG. 3A-3C,comprise a modular handguard 100 further comprising a plurality of slidefeatures 140 for interfacing with grooves 220 of an affixed handguard200. Slide features 140 provide rotational constraint of the modularhandguard 100 about the longitudinal axis 105 when mated to an affixedhandguard 200. It will be appreciated that slide features 140 maycomprise other engagement features known to those skilled in the art toprovide slidable engagement. It will be further appreciated that themating of a modular handguard is not limited to a slidable mating andmay utilize other mating features known to those skilled in the art.

Referring to FIG. 3A and FIG. 3B, certain embodiments comprise a modularhandguard having apertures 160 through an outer surface 115 of themodular handguard 100. These apertures 160 are provided for increasedventilation to the modular handguard 100 and a firearm to which themodular handguard 100 is affixed. Such apertures 160 may also be usedfor fixation purposes by inserting fastening hardware through anaperture 160 to affix an object to the modular handguard 100. Themodular handguard 100 may further comprise threaded apertures 165 forattachment of accessories or peripheral devices using threadedfasteners. It may be desired for a modular handguard 100 to haveapertures 160 and threaded apertures 165 configured to match theapertures 160 and threaded apertures 165 of an affixed handguard, asshown in FIG. 3A. However, some embodiments seen in, FIG. 3B, haveapertures 160 and threaded apertures 165 which differ in configurationfrom that of the affixed handguard 200. Threaded apertures 165 mayfurther comprise mechanical interface features such as counter-bores orcountersinks. The use of such mechanical interface features may be usedto provide increased fixation of a modular handguard 100 to an affixedhandguard 200. The use of such mechanical interface features may also beused to provide increased fixation of accessories or peripheral devicesto the modular handguard 100.

As shown in FIG. 3A and FIG. 3B, an inner surface 118 of the outer form110 of the modular handguard 100 is configured to slidably interfacewith the outer surface 210 of an affixed handguard 200. In suchembodiments, the cross-sectional profile of the internal surface 118 ofthe outer form 110 of the modular handguard 100, mimics thecross-sectional profile of the outer surface 210 of the affixedhandguard. Furthermore, the slide features 140 mate with grooves 220 inthe outer surface 210 of the affixed handguard 200. This configurationallows the modular handguard 100 to slide over the outer surface 210 ofthe affixed handguard. The mating of a modular handguard 100 with anaffixed handguard 200 provides an extension of the affixed handguard200. It will be appreciated that a modular handguard 100 may beconfigured so the attachment feature 150 of the modular handguard mateswith the attachment feature 250 of the affixed handguard so theattachment feature 150 of the modular handguard and the attachmentfeature 250 of the affixed handguard are contiguous.

While it will be appreciated that the inner surface 118 of the outerform, referenced in FIG. 3B, is configured to slidably mate with theouter surface 205 of an attached handguard, it will be furtherappreciated that the outer surface 115 of the outer form need not mimicthe outer surface 205 of the affixed handguard. The outer surface 115 ofthe outer form and the outer surface 125 of the inner form may beconfigured independently of an affixed handguard 200. In certainembodiments, the outer surface 115 of the outer form and the outersurface 125 of the inner form comprise profile shapes and featuresdesigned to promote increased airflow for cooling purposes orredirection of muzzle blast away from an operator and the firearm.

After slidable mating, certain embodiments of the invention (seen inFIG. 3C) may be constrained to prevent unintentional disassembly. Theconstraining of a modular handguard 100 to an affixed handguard 200 maybe accomplished with threaded fasteners engaged through an aperture 160or threaded aperture 165. When threaded fasteners are threaded throughthe threaded apertures 165, the threaded fasteners may be advanced untilthey contact the outer surface 210 of the affixed handguard 200. Incertain embodiments, threaded fasteners are passed through apertures 160to engage threaded apertures 165 in the affixed handguard. It will beappreciated that other methods of fixation may be used to constrain amodular handguard 100 to a fixed handguard 200. Certain methods offixation may be used to affix a modular handguard 100 to an affixedhandguard 200, which allow an operator to more easily remove a modularhandguard 100 from an affixed handguard 200. Other methods of fixationmay be used to affix a modular handguard 100 to an affixed handguard200, which provides a more permanent attachment of the modular handguard100 to an affixed handguard 200.

Certain embodiments of the present invention, shown in FIG. 4A, comprisemodular handguard 100 having an overall height 1000 of 6.77 cm (2.667in) having a profile of a multi-faceted form, such as an octagon, and anattachment feature 150. Such embodiments further comprise an overallwidth 1010 of 6.1 cm (2.4 in). The modular handguard 100, furthercomprises a hollow form with a substantially circular profile having aradius 1040 of 2.4 cm (0.95 in). Furthermore, such embodiments comprisea first facet width 1030 of 1.98 cm (0.779 in) and a second facet width1020 of 2.4 cm (0.932 in). It will be appreciated that a modularhandguard 100 may comprise other profiles, such as those consistent withthe profile of an attached handguard.

Certain embodiments of the present invention, shown in FIG. 4B, comprisea handguard having an overall height 1000 of 6.78 cm (2.667 in) andoverall length 1070 of 12.7 cm (5.0 in). Other embodiments comprise anoverall length 1070 of 22.9 cm (9.0 in). It will be appreciated that theoverall length 1070 of the modular handguard may be of any length, butpreferably of a length that extends the handguard no further than themuzzle-end of a barrel. It will be further appreciated that themuzzle-end of a barrel may be extended with the addition of a suppressoror other devices which may affix to the muzzle end of a barrel. Suchembodiments have an inner form 120 offset from an outer form 110 at anoffset length 1080 of 2.54 cm (1.0 in). It will be appreciated that theoffset length 1080 may vary.

Certain embodiments as shown in FIG. 4B, have apertures 160 and threadedapertures 165 through an outer surface 115 of the modular handguard. Incertain embodiments, the aperture distance 1110 between a first andsecond aperture 160 is 2.54 cm (1.0 in). The distance between threadedapertures 165 and an adjacent aperture 160 is 1.23 cm (0.485 in).

Certain embodiments, as shown in FIG. 4C, comprise an octagonal profilewith an outer form 110 having an internal width 1130 of 5.50 cm (2.164in), and a facet width 1180 of 1.78 cm (0.7 in). Such embodimentsfurther comprise slide features 140 having a tapered form with a topwidth 1160 of 0.295 cm (0.116 in), a height 1190 of 0.24 cm (0.094 in),and a base fillet radius 1170 of 11 mm (0.042 in). Such embodiments havean opposing slide feature spacing 1150 of 5.16 cm (2.03 in) and opposingfacet distance 1130 of 5.50 cm (2.164 in). It will be appreciated thatsuch embodiments are configured to slidably mate with an affixedhandguard. The above disclosed dimensions may vary dependent upon theaffixed handguard for which the modular handguard 100 is configured toengage with.

While various embodiments of the present invention have been describedin detail, it is apparent that modifications and alterations of thoseembodiments will occur to those skilled in the art. However, it is to beexpressly understood that such modifications and alterations are withinthe scope and spirit of the present invention. Further, the inventionsdescribed herein are capable of other embodiments and of being practicedor of being carried out in various ways. In addition, it is to beunderstood that the phraseology and terminology used herein is for thepurposes of description and should not be regarded as limiting. The useof “including,” “comprising,” “having,” or “adding” and variationsthereof herein are meant to encompass the items listed thereafter andequivalents thereof, as well as, additional items

What is claimed is:
 1. A modular handguard for attachment to a fixedhandguard comprising: an outer form comprising an inner surfaceconfigured to be disposed over an outer surface of an affixed handguard;an inner form comprising an outer surface and a hollow form, said innerform further comprising a first end offset from a first end of saidouter form; said outer surface of said inner form being coincident withsaid inner surface of said outer form; said first end of said inner formhaving an offset from said first end of said outer form.
 2. The modularhandguard of claim 1, wherein said inner form is inset from said outerform along a longitudinal axis.
 3. The modular handguard of claim 2,wherein said inner form is inset from said outer form a distance of 2.54cm (1.0 in).
 4. The modular handguard of claim 1, wherein said innerform further comprises a mechanical stop.
 5. The modular handguard ofclaim 1 further comprising apertures through an outer surface of saidouter form.
 6. The modular handguard of claim 5 further comprisingthreaded apertures through said outer surface of said outer form.
 7. Themodular handguard of claim 1, wherein said outer form further comprisesslide features coincident with said inner surface of said outer form andsaid slide features are configured to mechanically engage with saidaffixed handguard.
 8. The modular handguard of claim 1, wherein saidinner form further comprises an attachment feature.
 9. The modularhandguard of claim 8, wherein said attachment feature is coincident withsaid mechanical stop and said attachment feature is configured to abutan attachment feature of said affixed handguard, wherein said attachmentfeature of said modular handguard and said attachment feature of saidaffixed handguard are contiguous.
 10. The modular handguard of claim 1,wherein said modular handguard is manufactured from a polymeric materialhaving a melting point above 200° C. (392° F.).
 11. A modular handguardcomprising: an inner form having an inner surface and an outer surface,said outer surface of said inner form having similar cross-sectionalprofile to an affixed handguard; an outer form having an inner surfaceand an outer surface with the profile of said inner surface of saidouter form matching said cross-sectional profile of said outer surfaceof said inner form; said inner form having a length parallel with alongitudinal axis, said length of said inner form being shorter than alength of said outer form parallel with said longitudinal axis; anattachment feature affixed to said inner form parallel to saidlongitudinal axis; said inner form and said outer form parallel saidlongitudinal axis with a first end of said inner form being offset froma first end of said outer form; a mechanical stop coincident with saidfirst end of said inner form; slide features coincident with said innersurface of said outer form; mechanical interlock features; and saidslide features extending from said first end of said outer form to saidfirst end of said inner form; wherein said inner surface of said outerform is configured to be slidably mated with an outer surface of saidaffixed handguard, and said mechanical stop is configured to abut afirst end of said affixed handguard, wherein said attachment feature ofsaid modular handguard and said attachment feature of said affixed arebeing contiguous.